Children with developmental language impairments have long been suspected to have difficulties accessing words in their lexicons, based on evidence that they are slower and less accurate than their normally achieving peers on measures of word naming, word recall, and word categorization. However, a variety of recent evidence suggests that the methods and stimuli employed in such comparative investigations have not been controlled sufficiently to enable deficits in lexical access to be distinguished from deficits in the other cognitive, linguistic and motoric operations needed to perform such tasks. Further, no empirical evidence exists concerning language-impaired children's ability to identify words in spoken input, one of the most basic and crucial language processing tasks. The objectives of the proposed investigation are to determine (1) whether language-impaired children recognize familiar and unfamiliar spoken words presented in isolation as readily as their normally achieving peers; (2) whether variations in familiarity affect word recognition performance similarly in the groups; (3) whether the groups' spoken word recognition is influenced similarly when syntactic cues varying in acoustic salience are presented immediately before the target word; and (4) whether the groups differ with respect to developmental changes in word recognition performance. The successive forward gating paradigm (Grosjean, 1980; 1985), in which systematically incremented portions of an input signal are presented until word recognition occurs, will be employed in two studies of well- defined groups of language-impaired and normally achieving subjects in four age ranges (5-7, 8-10, 11-13 and 14-16 years). Results will provide evidence on the question of whether basic deficits in spoken word recognition are among the factors contributing to language-impaired children's poor performance on a wide range of language processing tasks.